 |
|
以作者查詢圖書館館藏 、以作者查詢臺灣博碩士 、以作者查詢全國書目 、勘誤回報 、線上人數：15 、訪客IP：18.217.140.32
姓名 林筵捷(Yen-chieh Lin) 查詢紙本館藏 畢業系所 太空科學研究所 論文名稱 模擬電離層E層電子濃度與散塊E層的發生機制
(Model simulation of E region electron density and Sporadic E layers)相關論文 檔案 [Endnote RIS 格式]
[相關文章]
[文章引用]
[完整記錄]
[館藏目錄]
[檢視]
- 本電子論文使用權限為同意立即開放。
- 已達開放權限電子全文僅授權使用者為學術研究之目的，進行個人非營利性質之檢索、閱讀、列印。
- 請遵守中華民國著作權法之相關規定，切勿任意重製、散佈、改作、轉貼、播送，以免觸法。
摘要(中) 本篇論文模擬電離層E層的電子濃度與因風切效應所引發的散塊E層發生機制。為了得知E層的電子濃度，我們利用E層中存在的五個離子(NO+、O2+、N2+、O+、Fe+)濃度加總來推算電子濃度。一開始單純只考慮經由光化學作用(產生作用與消失作用)產生的背景電子濃度分佈，則模擬的方法為：把隨高度、時間變化的離子產生率與離子消失率代入離子的連續方程式，以Runge-Kutta Method來解此連續方程式(一階微分方程式)，如此可得到各個離子濃度隨著高度與時間變化的分佈。
接著我們模擬潮汐風場造成散塊E層的發生現象。在E層，因離子碰撞頻率大於離子旋繞頻率，緯向潮汐風可藉由U×B drift導致離子在高度上有上下移動，當上層緯向風為西風、下層緯向風為東風，則會使離子在垂直漂移速度的輻合區域內累積，形成散塊E層。依上述想法，潮汐風造成的離子垂直漂移速度亦即為連續方程式中離子的傳輸項。接著把傳輸項代回連續方程式，以Crank-Nicholson Method來解此連續方程式(二維一階微分方程式)，如此可見因風切效應所造成的散塊E層發生現象。
摘要(英) In this study, we not only simulate height-time variations of background electron density of E region ionosphere but also study the formation of Sporadic E layers that is highly associated with the neutral wind shear. In order to model the electron density of E region ,we calculate the densities of NO+、O2+、N2+、O+、Fe+ that are assumed to consist in the ions in E region. The initial condition of the simulation is the photochemical equilibrium in E region, we calculate theoretical production rate and loss rates of the ions and substitude them into continuity equation to solve the first-order partial differential equation in accordance with Runge-Kutta method.
We then model the tidal wind that is responsible for the formation of Sporadic E layers. In the lower E region, the zonal neutral wind is the primary factor causing vertical ion drifts, which is the physical process of U×B dynamo in E region. Therefore, it requires that the zonal neutral wind with weatward in upper and eastward in the lower E region will result in ion convergence in northern hemisphere. The Sporadic E layers will occur at the region where the ion converges. With this configuration, the vertical ion drift velocity induced by tidal wind consititudes the transport term in continuity equation. Once the transport term is considered in the continuity equation, we use the Crank-Nicholson method to solve the resulting partial differential equation. The result indicates that a sporadic E layers indeed occurs at the regions where the ion are converged in the node of the neutral wind shear.
關鍵字(中) ★ 連續方程式
★ 解微分方程式
★ 散塊E層
★ 模擬
★ 電離層E層
★ 電子濃度關鍵字(英) ★ sporadic E
★ E-region
★ runge-kutta
★ continuity equaiton
★ electron density
★ simulation
★ Model論文目次 摘要 i
Abstract ii
目錄 vi
圖目錄 x
表目錄 xiv
第一章 前言 1
1.1研究動機與論文簡介 1
1.2模型的物理過程圖 3
第二章 理論基礎 6
2.1地球大氣層簡介 6
2.1.1中性大氣結構 6
2.1.2大氣結構的靜力方程式 9
2.2電離層簡介 11
2.2.1電離層的結構 11
2.2.2電離層的歷史 13
2.2.3 D層與E層簡介 15
2.3散塊E層與風切理論 17
2.4連續方程式 20
2.4.1太陽輻射的吸收 22
2.4.2查普曼函數 26
2.4.3產生率(Production Rate) 29
2.4.4消失率(Loss Rate) 31
2.4.5傳輸項(Transport term) 33
2.5大氣層中一氧化氮分子與鐵濃度計算 34
2.5.1一氧化氮分子濃度計算 34
2.5.2鐵原子濃度計算 42
第三章 模擬過程與參數 46
3.1五個離子粒子的連續方程式與反應速率常數 47
3.2四個大氣氣體濃度與鐵原子濃度介紹 50
3.2.1 [O2]、[N2]、[O]的濃度 51
3.2.2 [NO]的濃度 54
3.2.3 [Fe]的濃度 56
3.3光通量 62
3.4離子產生率 67
3.4.1離子產生率 68
3.4.2夜間加入其他輻射源之離子產生率 72
3.5離子垂直漂移速度 76
3.5.1 潮汐風場模型 77
3.5.2 HWM07模型 80
3.5.3 離子垂直漂移速度 82
3.6數值模擬方法與初始條件 84
3.6.1 Runge-Kutta Method 85
3.6.2 Crank-Nicholson Method 86
3.6.3初始條件 90
備註一：太陽天頂角計算方法 92
備註二：光吸收截面積 93
備註三：光離化截面積 96
備註四：[O2]、[N2]、[O]、[NO]的離化機率 99
備註五：Second-order Runge-Kutta推導 101
備註六：O2+、NO+、Fe+的初始值計算過程 103
第四章 模擬結果與討論 104
4.1 Fortaleza地區電子濃度與散塊E層模擬現象 105
4.1.1 Fortaleza地區E層背景離子濃度、背景電子濃度 105
4.1.2 Fortaleza地區散塊E層模擬結果 109
4.1.3 Fortaleza地區模擬結果與IRI模型和Abdu et al.,[2007]結果比較 111
第五章 結論與未來展望 114
5.1結論 114
5.2未來展望 115
參考資料 118
參考文獻 ﹝1﹞ A. J. Carrasco, I.S. Batista, and M. A. Abdu, “Simulation of the sporadic E layer response to prereversal associated evening vertical electric field enhancement near dip equator”, Journal Of Geophysical Research, Vol. 112, 2007
﹝2﹞ K. Davies, Ionospheric Radio, 1989
﹝3﹞ Kelly, M. C., The Earth’s Ionosphere: Plasma Physics and Electrodynamics, 6pp., Academic, San Diego, 1989
﹝4﹞ R. W. Schunk, A. E. Nagy, Ionospheres, 356pp., Cambridge, 2000
﹝5﹞ Chapman, S., “The absorption and dissociative or ionizing effects of monochromatic radiation in an atmosphere on a rotating earth”, 2, Grazing incidence, Proc, Phys. Soc. London, 43,483, 1931.
﹝6﹞ F. L. Smith, Cody Smith, “Numerical evaluation of chapman’s grazing incidence integral ch(ηp, χp) ”,Journal of geophysical research,vol.77, 1973
﹝7﹞ Swider, W., Jr., The determination of the optical depth at large solar zenith distances, Planet, Space Sci., 12, 761, 1964
﹝8﹞ Rishbeth, H., and O. K. Gariott, Introduction to Ionospheric Physics, p.96, Academic, New Your, 1969
﹝9﹞ Banks P. M., and G. Kockarts, Aeronomy, Academic, San Diego, Calif., 1973
﹝10﹞ J. E. Titheridge, Model results for the ionospheric E region: solar and seasonal changes, Ann. Geophysicae 15, 63-78, 1996
﹝11﹞ Fesen, C. G., D. W. Rusch, and J.-C. Gerard, The latitude gradient of the NO peak density, J. Geophys. Res., 95, 19052-19059,1990.
﹝12﹞ Magdalena Helmer and John M.C. Plane, “A model of meteoric iron in the upper atmosphere. ”, Journal Of Geophysical Research, Vol.103,1998
﹝13﹞ A. D. Danilov and U. A. Kalgin, Seasonal and latitudinal variations of eddy diffusion coefficient in the mesosphere and lower thermosphere.,Journal of Atmospheric and Terrestrial Physics, Vol. 54 1992
﹝14﹞ Theodore L. Brown, The Chemistry of Metallic Elements in the Ionosphere and Mesosphere,1973
﹝15﹞ L. N. Carter , J. M. Forbes, Global transport and localized layering of metallic ions in the upper atmosphere. Ann. Geophysicae, 1999
﹝16﹞ D. M. Hunten, R. P. Turco, O. B. Toon, Smoke and Dust Particles of Meteoric Origin In the Mesosphere and Stratosphere. Atmosphere Science, 1980
﹝17﹞ T. J. Kane, C. S. Gardner, Structure and Seasonal Variability of the Nighttime Mesospheric Fe Layer at Midlatitudes,JGR,1993
﹝18﹞ Chen, W. M., and R. D. Harris, An ionospheric E-region nighttime model, J. Atmos. Terr. Phys., 1971
﹝19﹞ M. K. Rees, Physics and chemistry of the upper atmosphere, Cambridge, 1989
﹝20﹞ E. Turunen, H. Matveinen, J. Tolvanen and H. Ranta, D-region Ion Chemistry Model,
﹝21﹞ D. F. Strobel and T. R. Young, The Nighttime Ionosphere: E Region and Lower F Region
﹝22﹞ Abdu, M. A., J. Macdougall, I. S. Batista, J. H. A. Sobral, and P. T. Jayachandran, Equatorial evening prereversal electric field enhancement and sporadic E layer disruption: A Manifestation of E and F region coupling, J. Geophys. Res., 2003
﹝23﹞ Morton, Y. T., J. D. Mathews, and Q. Zhou, Further evidence for a 6-h tide above Arecibo, J. Atmos. Terr. Phys.,1993
﹝24﹞ Steven C. Chapra 著, 應用數值方法, 王晉中譯, 美商麥格羅-希爾國際股份有限中司, 2005
指導教授 朱延祥(Yen-Hsyang Chu) 審核日期 2010-7-20 推文 plurk
funp
live
udn
HD
myshare
netvibes
friend
youpush
delicious
baidu
網路書籤 Google bookmarks
del.icio.us
hemidemi
facebook
twitter
google
reddit